#include <stdio.h>
#include <unistd.h>
#include <string.h>
int main()
{
    const char*p1="hello printf\n";
    printf(p1);
    const char*p2="hello fprintf\n";
    fprintf(stdout,p2);

    fork();
    const char*p3="hello write\n";
    write(1,p3,strlen(p3));
    return 0;
}
